A United Airlines employee posted security codes online that are used to access the cockpit, possibly compromising security, according to a report from the Wall Street Journal.
Access codes are a security measure airlines use to request access to the cockpit.
According to the Wall Street Journal, the flight attendant who posted the information online did so by accident.
In a statement to Business Insider, United said that it uses various ways, besides access codes, to ensure security.
"We have learned that some cockpit door access information may have been made public. The safety of our customers and crew is our top priority and United utilizes a number of measures to keep our flight decks secure beyond door access information," the company said in a statement to Business Insider.
"In the interim, this protocol ensures our cockpits remain secure. We are working to resolve this issue as soon as possible."
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All of United Airlines' recent PR nightmares
All of United Airlines' recent PR nightmares
1. United Airlines Flight 3411
Footage of Dr. David Dao being dragged off United Airlines Flight 3411 from Chicago, Illinois, to Louisville, Kentucky, went viral on April 10.
The incident, in which Dao lost teeth and broke his nose, sparked international uproar and turned into a public relations nightmare for the carrier.
Dao will be suing the company, according to his attorney.
2. Second United Airlines passenger comes forward
Amid the social media firestorm set off by Dr. Dao's incident, a second passenger came forward to say that he, too, recently experienced mistreatment on a different United Airlines flight.
Geoff Fearns, 59, told KCAL he was removed from his first-class seat on a flight from Kauai, Hawaii to Los Angeles, California last month.
Although Fearns said he tried to resist the flight attendant's orders at first, he eventually caved once she threatened to have him put in handcuffs.
3. Scorpion falls from overhead bin and bites passenger
A Canadian couple's Mexican vacation came to an unfortunate end when they were flying home to Calgary from Houston on April 11.
Richard and Linda Bell were on a United Airlines flight when a scorpion fell from an overhead bin onto Richard's head.
He dropped it on his plate, then picked it up again, when the scorpion stung him.
The animal was stomped on and thrown in the toilet.
Emergency services were called in, but Bell was reportedly not in distress. He declined medical treatment.
4. Woman claims she was sexually harassed by drunk man on United Airlines flight
A New Jersey woman said that United Airlines flight attendants continued to serve alcohol to a visibly inebriated passenger after she complained that he sexually harassed her.
Jennifer Rafieyan was traveling from Newark, New Jersey, to Phoenix, Arizona, with her 12-year-old daughter when the drunken passenger was escorted onto the plane.
Over the course of the flight, Rafieyan said the man repeatedly groped her and rubbed her legs and knees, while occasionally kissing her hands and putting his head on her shoulder.
Rafieyan reported the passenger to a crew member after her daughter got up to use the bathroom, but it did little to help her situation.
"She said, 'I'm so sorry. We felt really bad putting him next to you, but there was nothing we could do. He was doing the same kind of stuff to the other flight attendant,'" Rafieyan recalled.
5. Couple kicked off United flight on way to their wedding
Michael Hohl and Amber Maxwell had boarded their flight when they noticed a passenger napping across the row they were supposed to be sitting in.
Instead of waking up the snoozing man, the pair decided to sit a few rows in front of their assigned seats.
Hohl said that after he and Maxwell sat down, a flight attendant asked if they were in their assigned seats. When the couple said no and explained why they had moved, Hohl said the attendant declined their request for an upgrade and asked them to return to their original seats.
Hohl said that although he and Maxwell did as they were told, a U.S. Marshall later boarded the flight and asked them to get off the plane.
6. United Airlines CEO's heart transplant comes under scrutiny
Following United Airlines CEO Oscar Munoz's apology over Flight 3411, people began questioning whether his wealth played a role in the heart transplant he received last year.
Munoz had a heart attack on October 15, 2015, one month after he took over as United's new CEO.
Less than three months later, he received a new organ.
Since the waiting list for a new heart was reportedly up to 4,200 people at the time, questions have risen about how he was able to get a new heart without waiting very long.
7. Dad accused of trafficking his own daughter on United plane
The wife of a Mexican man who was accused of trafficking his own 3-year-old daughter on a United Airlines flight spoke out about the incident on April 17.
Maura Furfey, a Spanish teacher and mother of three, says that her husband and daughter were returning from a trip to Mexico to visit her husband's mother and great-grandmother, "who they see but once a year."
Apparently another passenger, who Furfey says was "obviously inebriated," expressed concern to an airline employee that the fair-skinned child didn't look like her Mexican father, raising suspicion that he had kidnapped her.
The mother of three says she burst into tears when she learned the details of what her family had gone through.
8. United Airlines stock plummets $800 million amid controversy
United Continental lost about $800 million in total value the day after the video of Dr. Dao being dragged off Flight 3411 became a major news story.
Shares in the company declined about 3.8 percent in mid-morning trading, a steep drop for a major company like United.
9. Woman claims United Airlines employee forced her to back of plane in tears without explanation
A New York woman filed a $150,000 lawsuit against United Airlines, claiming she was forced from her business class seat to the back of the plane by an employee without any explanation during a flight last year.
Karen Shiboleth, a 24-year-old Columbia graduate, was traveling to London to attend a master's degree program at Kings College on September 10, 2016.
Shiboleth claims that ten minutes prior to take off, a United employee boarded the craft and demanded she vacate her seat in United BusinessFirst and move to the back of the plane.
The lawsuit alleges that nobody would explain to Shiboleth why she was being moved, and that when she expressed her confusion, the employee took her arm "without consent" and forced her to a middle seat in the back of the plane.
To make matters worse, the unidentified worker reportedly called her a "c--t" during the interaction, bringing Shiboleth to tears.
10. Professional golfer claims his clubs were snapped on United Airlines flight
An Australian professional golfer took to Twitter on April 24, claiming his golf clubs were destroyed during a recent United Airlines flight.
Veteran golf pro Matthew Goggin said he opened his checked bag after his trip, only to discover that his precious clubs were snapped in two.
"First time in 20+ years I've opened my bag to find this..." he wrote. "I was going to complain but I must admit I'm a little intimidated by United."
11. Giant rabbit mysteriously dies aboard United Airlines flight
Simon, a 35-inch behemoth, was traveling from London's Heathrow to Chicago's O'Hare to meet his new "celebrity owner" when he mysteriously died in the airline's care.
Annette Edwards, Simon's breeder, says that both she and Simon's buyer are extremely upset and confused by the incident.
"Simon had a vet's check-up three hours before the flight and was fit as a fiddle," Edwards said. "Something very strange has happened and I want to know what. I've sent rabbits all around the world and nothing like this has happened before."
Simon was the son of the world's current largest rabbit, Darius, who is a whopping 51 inches long.
The 10-month-old rabbit was reportedly on track to out grow his father and eventually steal his title.
Instead, the family was met with a Great Dane they had never seen before. Apparently, a United mix-up had sent Irgo all the way to Japan, which is where the Great Dane was meant to go.
13. Flight attendant forces passenger to place puppy in overhead bin. The puppy was later found dead.
United Airlines has apologized after a passenger's dog died Monday evening during a flight. The incident took place on United Airlines Flight 1284 from Houston, Texas to New York's LaGuardia Airport.
United Airlines' says PR team is hiring
Feeling up for a challenge?
There are currently three job openings in Houston, New Jersey, and California for a brand manager in the United public relations department.
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The airline did not state specifically what these other measures are. But according to the Wall Street Journal report, the airline also requires pilots to visually verify someone's identity before granting access to the cockpit.
According to the report, the company sent out a memo to employees notifying them that this information had been made public and reminding them to take extra steps when granting access to the cockpit. However, no delays have resulted thus far because of the incident, the Journal reported.
On April 9, Dao was dragged off flight 3411 by Chicago Aviation police officers after refusing to give up his seat on the full plane for airline employees. Other passengers on the place recorded the incident in a video that quickly went viral.
The footage sparked public outrage, not only against United but against the airline industry in general for its practice of overbooking seats and for its treatment of passengers.
As a result, United announced policy changes affecting both customers and employees. Some of the changes the company said it was implementing included more annual training for employees and an overall reduction in overbooking.